Google has introduced its own version of social search service, which it is calling "+1" or "plus one". Similar to Face book’s "like", it will encourage users of its web search engine to recommend useful search results.

It remains to be seen whether the service will become as popular as quickly as Face book’s “like” system has. It is clear, though, that Google will be using this information as part of its search algorithm; Matt Cutts, a Google search engineer, said as much to the Wall Street Journal, telling it the company plans to use the plus one recommendations "as a signal in our rankings."

One of Many

Make that one of many signals - new signals. Google has been keeping SEO marketers awake at night with all the changes it has been introducing to search. Most notably last month it introduced a change in its ranking algorithm designed to cull low-quality sites from its search rankings. Then it gave users the ability to ban sites they don't like from their search results. The latter move has not made its full impact felt yet on search. As Google put it, while it is not currently using the domains people block as a signal in ranking, it will be looking at the data and seeing whether it would be useful in its search evaluations.